eugkim

I recently had my 2 fuel pumps replaced. Unfortunately, the fuel gauge is now stuck at 1/4. The dealer says that the instrument cluster needs to be replaced at a cost of $3500. I did a search and found 2 similar cases, both with stuck gauges after fuel pump replacements. In both cases, a wire or tube from the pump apparently got tangled in the float in the tank. I spoke to a very experienced independent foreign car tech (won't work on Porsche) who immediately said the same thing has happened to him. I took it back to the dealer, told the service advisor about my thoughts, and got attitude - he said that "our tech would never do something like that. I doubt that's the problem." When the other advisor called me, she told me what the tech checked, and he apparently never broke open the fuel tank. At that point I was too disgusted with the dealer and took it to a local garage that I really trust.

I'm probably going to have to wait the weekend for him to check this out. Anyone have any thoughts or similar experience?

deilenberger

Take it back to the dealership and say "Hooeeey.."

When my pumps were replaced I had the same symptom. It was a wire that came loose on the fuel level sensor. Took them about 20 minutes to fix (most of the time spent pumping out the tank which I had just filled so they could open it up without flooding the car with fumes.)

eugkim

Thanks for the input, Don. I just got the Cayenne back, and sure enough, that was the problem. Before cracking open the fuel tank, he wanted to ground out the gauge to ensure that it was functioning first. Seems logical; kind of troubling that it wasn't checked by the dealer prior to recommending a $3500 replacement.

This episode supports what I've come to think about mechanics. I've become more reliant on the older, experienced guys who understand the problems and try to diagnose them before relying on the computers. It seems like many dealers are looking to simply replace parts to fix a problem.

Now I'm not sure what to do. I was about to pull the trigger on a new Audi S6 at the dealer. I told them I'd be reconsidering depending on how this service was handled. Now I'm not too confident that I can rely on them. The real benefit of using them is that they provide a loaner for every service, making it very convenient.

Jeroen Pipelers

Where is this fuel level sensor to be found? Mine is stuck empty.

scottl951

I had same problem and cause was a hose over the float on drivers side not allowing float to go all the way up. Glad to hear they fixed it.

Jeroen-Level sensors(floats) are in the tank. One on each side.

Jeroen Pipelers

Where do i look? Under the seats or under the car?

scottl951

I found a Touareg procedure on google. THey are the same. Access is under the rear seats. You'll see a perforated circle in the carpet. If it's still connected, ie-perf not cut, no one has been there before. Cut the perfs and under the carpeet you'll see a round metal plate held on by 4 nuts. On nut is under the seat bracket so that will have to come off. Under the plates is the tank access. Filter is on driver's side. Each side has a float that snaps onto the pump assembly. Testing equipment (piwis, pst2, durametic) should be able to to tell you which side is malfunctioning. Recommend tank being close to empty if cracking it open. And be sure to have new gaskets ready.

Jeroen Pipelers

does that mean our cars have the same fuel filter as a Touareg?

deilenberger

Yes - but it doesn't seem to be any cheaper (and it's a complex filter mechanism - the top of the pump assembly - with valves and all sorts of neat stuff that can go wrong.) It is replaced when it fails - not before. And it may never fail if you never get a tank of bad gas.

Jeroen Pipelers

have you seen this: http://www.ebay.com/itm/Power-Train-...4a3eb7&vxp=mtr

deilenberger

Interesting.. doesn't look at ALL like a Cayenne filter. Which being ebay doesn't really surprise me.

Here is the correct one - but even this looks different in some ways than the Cayenne filter (less hoses going to it for one thing..)

http://www.ebay.com/itm/Volkswagen-T...a0820d&vxp=mtr

So - I'll modify my statement.. "no".. (at least I don't think so, although I have seen discussion on using the Toureg fuel pumps in a P!G..)

Jeroen Pipelers

This is not your everyday fuel filter. Pretty expensive if you ask me.

scottl951

I got mine off Amazon for about $85.

spooltime

Bringing this thread back to life since it contains really good information, and many of our 955's are getting up there in age and miles (120K on mine) to the point where fuel pump replacements will become more common.

With mine, I had begun noticing a very strong smell of gasoline near the driver's side rear quarter panel when standing outside of the vehicle. I didn't really smell it inside the vehicle, but became convinced that with one wrong spark while the Cayenne was parked in the enclosed garage, the place would go up in flames based on the strong gas fumes. I let the fumes continue for several week before finally deciding to bite the bullet and take it to my dealer.

Hoping for only a vent valve problem, it turned about being the fuel pumps. They replaced both of them and the strong gas smell was gone. I topped off the tank upon leaving the dealer and drove home. Before shutting it off, I luckily just happened to notice that my fuel gauge was showing only 3/4 full even though I had driven just 14 miles. I knew my CTTS gas mileage sucks badly, but this was apparently a new low. So I go top it off again and the fuel gauge stays locked on 3/4 full. Okay, for sure there's a problem with the gauge.

That's when I found this thread and realized there were two primary possibilities - either the sending unit was unplugged, or one or more of the lines in the tank were binding with the sending unit causing it to not operate properly. I contacted my service rep and brought it back the following day for them to check it out. Mine turned out to be some misrouted line in the tank, and everything is working perfectly now. Just a PITA to have to take it back.

So my advice is that if you're replacing your own fuel pumps or having it done, let whoever is doing it to pay very close attention to the routing of the hoses in the tank so that they don't interfere with fuel gauge sending unit. It will save a lot of time and effort to get it done right on the first try.